Spray roses to protect the plants

against blackspot, mildew and aphids. Some gardeners will be happy to use a dual systemic insecticide and fungicide such as Rose Clear Ultra, but an organically-friendly alternative remedy for these fungal diseases is to spray with a homemade solution of one teaspoon of baking soda mixed with one gallon of water and a squirt of washing-up liquid. Heavy infestations of greenfly can be treated with an organically-approved pyrethrum-based spray, whose active ingredient is an extract from the flowers of

Tanacetum (Chrysanthemum) cinerariifolium

(available from fruithillfarm.com)

Sow some summer radishes

to add a peppery, crunchy kick to your salad bowl. Very fast-growing and easy to cultivate as long as you keep an eye on slugs/snails, these vegetables need a sunny spot and moist, fertile soil and are suitable for container growing. Look out for the varieties ‘Cherry Belle’ and ‘Scarlet Globe’.

Keep training the rapidly growing shoots of summer-flowering clematis

by gently tying new growth to wires/trellis to prevent them from forming a tangled thicket of stems.

Keep a constant, watchful eye out for side-shoots on cordon tomatoes

, and pinch them out whenever you find them (they grow from the leaf axils of the plant, where the leaf joins the main stem). But be careful not to mistake them for the developing blossoms, as without the latter you won’t get any fruit.

Garden centres are stocked full of trays of

bedding plants, which should be planted out now to guarantee a good display

all summer long. Don’t forget to include a few fine foliage plants such as the silver-leaved

Helichrysum petiolare

or

Plectranthus argentatus

.